1. Field of the Invention
This invention relates to vessel propulsion systems, and in particular to a modular hydraulic thruster system for vessel.
2. Background of the Invention
Marine thrusters typically mount on barges and flat boats, and are used as propulsion for these vessels. One type of marine thruster employs a prime mover such as a diesel engine driving a hydraulic pump, together known as a “power pack”, and the resultant pressurized hydraulic fluid may be employed to drive a propeller attached to a lower unit.
A number of designs exist for this type of flat boat propulsion system, with attendant problems. One problem is the lack of readily available instrumentation to depict important condition information such as the angle of thrust at which a given thruster is aiming relative to the centerline of the vessel to which it is attached, the power output being developed in terms of propeller revolutions per minute, the tilt angle of the thruster lower unit, the degree of extension or retraction of the thruster lower unit, and the condition of any clamps in the system (open or closed).
Another problem with existing marine thruster designs is the absence of a quick and easy means to add additional thrusters to the system, as required. It would be desirable to provide a modular hydraulic thruster system for vessel which provides the provisions for readily attaching additional thrusters as required for a flat vessel whose weight loading and/or thruster requirements may be changing.
It would also be desirable to provide a modular hydraulic thruster system for vessel which comprises indication capability including displays of the angle of thrust at which a given thruster is aiming relative to the centerline of the vessel to which it is attached, the power output being developed in terms of propeller revolutions per minute, the tilt angle of the thruster lower unit, the degree of extension or retraction of the thruster lower unit, and the condition of any clamps in the system (open or closed).